Average temperature the temperature in f in boston over a

Question

Question: AVERAGE TEMPERATURE The temperature (in °F) in Boston over a 12-hr period on a certain December day was given by

T = -0.05t³ + 0.4t² + 3.8t + 5.6    (0 ≤ t ≤ 12)

Where t is measured in hours, with t 0 corresponding to 6 a.m. Determine the average temperature on that day over the 12-hr period from 6 a.m. to 6 p.m.